A USB cable includes two USB connectors and a plurality of cable lines. Each USB connector includes a circuit board, a tongue board, a plurality of connection terminals, a signal processing IC, an isolated housing and a metal housing. The tongue board is connected with the circuit board. One end of the connection terminals are connected to the circuit board, and the other end of the connection terminals are set in the tongue board. The signal processing IC is electrically connected to the circuit board and further connected to the connection terminals. The isolated housing encapsulates the circuit board and the signal processing IC. The metal housing encapsulates the tongue board and the connection terminals. The signal processing IC encrypts data for transmitting externally through the connection terminals, and decrypts data received by the connection terminals to transmit to other end of the USB cable to be used.